The optical frequency comb is a spectrum of evenly spaced narrow laser lines. Optical frequency combs have revolutionized time and frequency metrology by linking microwave and optical frequencies. However, realizing their full potential in a broader range of applications such as 3D imaging, environmental sensing, LIDAR, and high-speed optical communications, is conditioned by the availability of inexpensive highly miniaturized devices. Progress in integrated optics towards chip-scale frequency combs has made significant strides in recent years. UGent has been at the forefront of this evolution. It has developed unique technologies in heterogeneous integration, enabling the long-missing functionality of optical gain on a chip. This unlocks the full integration of combs, in particular, in the infrared, but also in the near-infrared range (800-1100 nm), the key to sensing in water-dominated media as encountered in biological samples, e.g., in optical coherence tomography setting, food industry, and environmental sensing. In MOLOKAI UGent will engage in a close collaboration with the group at MBI which is the pioneer of the applications of frequency combs applied to dual-comb interferometry and, in particular, the initiator of the extension of frequencycomb techniques to 3D imaging, and to Raman spectroscopy. In this way in MOLOKAI, we aim to leverage the latest breakthroughs in chip-scale frequency-comb technology to transition these technologies in a real-life setting. MOLOKAI will work further on our initial dual-comb results to make a broadband on-chip interferometer. For that, MOLOKAI will collaborate closely with IBSEN Photonics, a spectrometer company, to make high-resolution spectrometers that can be used to read out Bragg sensors in fibers.
Next, the dual-comb technology will be ported to a GaAs-on-silicon nitride platform. Here dual-comb systems allow for the prospect of high-resolution images.